The closest some cruisers get to wildlife is when they lift a glass of Wild Turkey at Panda Express Cancún.

But I prefer the more adventurous kind of cruises you experience on almost any ship from G Adventures, Lindblad Expeditions and Hurtigruten and Silversea's three expedition ships, to name a few. These can often turn into full-throttle immersions into nature. 

Here's a Visual List of some favorite wildlife and marine life photos I've spotted on Cruiseable. (Go ahead, create your own! It's fun, fast and free.)